This invention relates to an opening forming device which may be used to provide modular or other pre-set and later readily locatable, cable passage openings in poured or otherwise formed materials on a planar deck or other support, forming a floor, wall or other planar structural member. The device has features enabling it to be thus readily activated to leave openings or voids in the structural member at desired stations, for positioning articles therein, and is adaptable for use in numerous applications-for example, and without limitation thereto, in connection with building procedures, to provide voids, for example, at precalculated spaced intervals, while maintaining the UL rating of the structural member at all times.
The device is adapted for use, for example, in building construction wherein it is desired to provide openings which may be selectively activated to receive electrical insert devices for connection of cables in or passed through the building wall, floor, raceways, etc., for connection with accessory devices. It has heretofore been necessary, in such cases, to drill holes in the structural member to receive inserts or other devices. In some cases, miscellaneous objects readily at hand such as tin cans, etc. were secured to deck forms and the material poured therearound. Such random, unreliable, haphazard, inaccurate inprovisations and expedients, resulted in reduction of Underwriters' Laboratory ratings; objects such as tin cans, being heat conductors, lowered the heat resistance ratings which would otherwise apply to a concrete or other floor; furthermore, such prior improvisations were unpredictable, unreliable and impractical, time-consuming, awkward and costly and inaccurate, and entailed delay.